Inking mechanism for printing machines



March 25, 1952 w. F. HUCK INKING MECHANISM FOR PRINTING MACHINES Filed May 50, 1945 INVEN TOR. @WM. 7%

Patented Mar. 25, 1952 IN KING MECHANISM FOR.- PRINTING MACHINES William F. Huck, Forest Hills, N. Y., assignor to R. Hoe & 00., Inc., New York, N. Y., a corporation of New York Application May 30, 1945, Serial No. 596,625

3 Claims. (01. 137- 78) This invention relates to rotogravure printing machines and more particularly to inking mechanism for such machines in which the ink used contains a highly volatile solvent or thinner and it is desirable to maintain the proper proportion of solvent in the ink, in order to produce high quality printing.

The ink solvent or diluent in the inking system of certain printing machines constantly evaporates and thus requires replacement at frequent intervals, to maintain the ink solvent and other ingredients of the ink in their proper proportions, As constant attention of the operator is required to maintain the proper ink mixture when the replacement of solvent is done manually, and at such intervals that no variation in the printing will be noticeable, it is desirable that replacement of ink solvent be done automatically, and that the mechanism for doing it be as critical to changes in the mixture as is practical.

An object of this invention is to provide an improved mechanism for automatically accomplishing the replacement of solvent evaporated from ink being used in a printing machine.

A more specific object is to provide, in an inking mechanism for a rotogravure printing machine, means responsive. to variations in solvent content of the printing ink, to automatically control the addition of ink solvent as required to replace solvent lost by evaporation and maintain the proper proportion of solvent in the ink.

With the foregoing and other objects in view, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter shown, described I and claimed. 2

The drawing illustrates the combination and arrangement of parts and details of construction of an inkin mechanism for a rotary intaglio printing machine embodying the features and principles of this invention.

Referring now to the drawing, the reference numeral M denotes a web passing between a printing cylinder I2 and an impression cylinder proper proportions to produce high quality print ing on the web H by the printing cylinder i2.

A mixing chamber 2| is disposed in the system between the reservoir and the pump 96 and a needle valve 22 is disposed in the system between the pump I B and the pipe IS. The needle valve 22 is for the purpose of providing a man-,- ually adjustable restriction to the flow of ink mixture from the pump Hi to the pipe I8 and to thereby create apressure on the pump side of the valve 22. A tube 23 is connected to the system between the pump l6 and the needle valve 22 and leads to a pressure indicator, or gauge 24 of -well-' known construction having a shaft 31 carrying an indicating pointer 25 that is rotated in relation to a dial 26 when the pressure in the tube 23 varies A tube 21 leads from a solvent tank 28 to a valve 29 arranged to be controlled and operated by means of an electrical circuit, herein shown in simplified form as it forms no part of the invention. A tube 32 leads from the valve 29 to and into the mixing chamber 2|. An electrical con ductor 33 leads from a line terminal L2 to one terminal of a solenoid 3|,and an electrical conductor 3-1 leads from the other terminal of the solenoid to a plate 35 located on but insulated from the dial 26. A contact pin 36 is adjustable along the plate 35 and may be positioned manually at the point on the dial at which it is desired to operate the valve 29. Thus when the pointer 25 reaches the contact pin 36, a circuit is made through the plate 35, pin 38, pointer 25, shaft 31 and conductor 38 to a line wire LI energizing the solenoid 3| to open the valve 29 and allow solvent to flow from the tank 28 to the mixing chamber 2|, to be mixed with the ink mixture I3. The printing cylinder |2 rotates in an ink fountain M in which a supply of ink I5 is maintained by an ink pump It. The ink pump i6 is connected to a reservoir H from which it pumps ink to the fountain M through a suitable pipe Hi. The desired level of ink i5 is maintained in the fountain M by means of an overflow pipe |9 which leads back from the fountain M to the reservoir H. The ink I5 in the system is composed of a being pumped from the reservoir l1 into the pipe H3. The valve 29 has a handle 3|] that may be adjusted to vary the rate of flow of solvent from the tank 28 when the valve is opened by the solenoid. Adjusting the pin 36 along the dial 26 in the di rection of increasing pressure will keep the sole noid 3| from being energized until the liquid dis. charged from the pump I6 has attained a relatively high viscosity or consistency, whereas adjusting the pin 36 in the reverse direction allows the solenoid 3| to operate when the liquid is at a relatively low viscosity.

Addition of solvent into the ink flowing from the reservoir l1 decreases the viscosity of the mixture whereby a greater flow will pass through the needle valve 22 and the fluid pressure at the inlet side of the valve 22 will be reduced and so mixture of suitable materials and ink solvent in indicat d by the gauge 2 When the desired proportion of solvent in the ink mixture has been obtained the pointer 25 will be moved out of contact with the contact pin 36 de-energizing the solenoid and allowingthe valve 29 to close, thus shutting off the flow of solvent to the mixing chamber 2|. Gradual evaporation of the solvent in the ink mixture as'it is being used will increase the viscosity of the mixture and gradually less ink mixture will pass through the restricted opening in the needle valve 22 whereby a gradual increase in pressure in the tube 23 and in the gauge 24 will result. When this pressure reaches a pre-determined amount, the pointer 25 will contact the contact pin 36 to again energize the solenoid and open the valve 29. By adjusting the needle valve 22, variations in the viscosity of the ink mixture may be made. Manually adjusting the needle valve 22 to decrease the amount of liquid that can flow therethrough, increases the pressure on the gauge 24 and thus causes the-solenoid 3| to open the valve 29 when the liquid is at a relatively low viscosity, whereas adjustment of the needle valve to increase the flow will decrease the pressure on the gauge 24 and require a relatively high viscosity in the liquid before the valve 29 will open. After proper adjustment of the needle valve 22 and of the pin 36, the mechanism of this invention will automatically maintain the proper and desired proportion of solvent and ink in the ink mixture to insure high quality printing.

It will be understood that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being made to the. claims rather than to the foregoing description to indicate the scope of the invention.

What I claim is:

1. An ink circulating system for a printing machine including an ink fountain, an ink reservoir, a suitably driven pump having a first connection through which it receives ink from the reservoir tion.

2. 1he combination according to claim 1 in which the said first connection includes a mixing chamber into which solvent is admitted to be mixed with the ink passing to the pump.

3. The combination according to claim 1 in which the said restricting means consists of a valve for throttling the flow of ink to thereby regulate the fluid pressure where it is discharged from the pump.

WILLIAM F. HUCK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,902,635 Bratkowski Sept. 5, 1911 1,178,193 Trimbey Apr. 4, 1916 1,604,672 Albersheim Oct. 26, 1926 1,641,673 Hall Sept. 6, 1927 1,789,386 Kalle Jan. 20, 1931 1,838,710 Schur Dec. 29, 1931 2,055,272 Weiss Sept. 22, 1936 2,262,573 Bender Nov. 11, 1941 2,325,573 Thompson July 27, 1943 2,339,991 Hagy Jan. 25, 1944 FOREIGN PATENTS Number Country Date.

204,232 Great Britain Sept. 27, 1923 540,881 Germany Aug. 14, 1929 537,497 Germany Mar. 8, 1931. 

